Nowadays, wireless network technologies have been utilized widely. In order to provide different qualities of service (QoS) in different environments, various network protocols have been developed. Among these network protocols, WiMAX (Worldwide Interoperability for Microwave Access) and LTE (Long Term Evolution) have become popular wireless network system specifications.
In existing wireless networks, a particular management system (e.g., an Element Management System (EMS) or an Operation and Maintenance (O&M) system) of the core network configures operations of base stations and relay stations respectively during installation of base stations and relay stations.
Furthermore, to improve performance of the whole wireless system, relay stations now perform most of functions that were previously possessed by base stations only. In this case, a base station can provide communication between a relay station and a core network. However, there is no particular protocol mechanism between the base station and the relay station, which allows them to learn operation modes of each other. As a result, the management system of the core network is unaware of the signal transmission conditions between the base station and the relay station or the load conditions of the both when allocating radio resources of the wireless system to the base station and to the relay station. Therefore, it would be impossible to achieve an optimal transmission efficiency in signal transmissions between the base station, the relay station and user equipment (UE).
Moreover, in the existing wireless networks, manual adjustment via the management system of the core network is required when it is desired to change allocation of the radio resources.
On the other hand, when the base station needs to use the same radio resources for other applications (e.g., broadcasting) without coordinating allocations of the radio resources, a collision in use of the radio resources might be caused between the base station and the relay station.
Accordingly, significant efforts are still required in the art to establish a particular protocol mechanism for appropriately allocating radio resources to base stations and relay stations in a dynamic way.